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31.
Two polymorphic dinucleotide (CA) repeat clones were isolated from cosmids, cCI8-1121 and cCI8-1199, mapped to chromosome 8p11.2-p12.  相似文献   
32.
Human prostate cancers frequently show loss of heterozygosity at loci on the short arm of chromosome 8. In order to take a step toward isolation of the putative tumor suppressor gene(s) on 8p via positional cloning, we performed high-resolution deletion mapping in 46 prostate cancers (stage B, 20 cases; stage C, 8 cases; endocrine therapy-resistant cancer death, 18 cases) using new 12 restriction fragment length polymorphism markers for this chromosomal region. Allelic losses were observed in 25 of the 44 cases (57%) that were informative with at least one locus. Detailed deletion mapping defined a 1.2 Mb commonly deleted region at 8p22-p2 1.3 flanked by markers cMSR-32 and C18- 105 1. A second region of common deletion was identified between C18-1312 and C18-494 at 8p21-8p11.22, suggesting that at least two tumor suppressor genes associated with prostate cancer are present on chromosome arm 8p. Allelic losses on 8p were observed more frequently in the cancer death cases (14/17, 82%) than in early-stage tumors (11/27, 40%; P < 0.01, Fisher's exact test). In two out of 7 patients for whom DNA was available from metastatic cancers as well as from normal tissues and primary tumors, the primary cancer foci had no detectable abnormality of 8p, but the metastatic tumors showed loss of heterozygosity. These results suggest that inactivation of tumor suppressor genes on 8p plays an important role in the progression of prostate cancer. © 1995 Wiley-Liss, Inc.  相似文献   
33.
After radiofrequency ablation (RFA), hepatocellular carcinoma undergoes complete necrosis and an ongoing necrosis that is irreversible and characterized histologically by disrupted cell outlines, homogenous cytoplasmic eosinophilia, and preserved nuclear staining, with the cells appearing quite distinct from viable cancer cells. Antibody to detect single-stranded DNA (ssDNA) specifically labeled nuclei in the setting of ongoing necrosis, but not viable tumor cells, whereas human mitochondrial antibody labeled the cytoplasm of viable cells but not cells of ongoing necrosis. The results demonstrate that RFA causes denaturation of both DNA and proteins and that the immunohistochemistry of ssDNA and mitochondrial protein is useful in detection of ongoing necrosis after RFA and provides pathological information on the validity of this procedure.  相似文献   
34.
Primary ovarian angiosarcoma is extremely rare. Only 16 cases have histologicaliy been reported to date In the Ilterature. A case of angiosarcoma arising In the right ovary of a 46-year-old female is presented. Grossly, the resected right ovary was completely replaced by a solid tumor mass, which revealed multiple necrotic and/or hemorrhagic foci. This case revealed the typical histological features of angiosarcoma with sinusoldal and solid patterns of anaplastic tumor cells. Immunohlstochemically, tumor cells were strongly and diffusely positive for CD31 and CD34, in particular, along the cytoplasmic membrane of the tumor cells. Ultrastructurally, tumor cells possessed the intermediate junctions between tumor cells, discontinuous basal laminae attached to the irregularly shaped blood vessels and occasional cytoplasmic pinocytotlc vesicles. These findings confirmed the case as being one of angiosarcoma of the ovary. The patient died 9 months after surgery as a result of developed multlfocal brain metastases. A total of 17 cases reported as primary ovarian anglosarcoma, including this presented case, are clinicopathologically reviewed.  相似文献   
35.
36.
The inflammatory bowel diseases (IBDs), Crohn's disease (CD) and ulcerative colitis, are chronic inflammatory disorders of the digestive tract. The pathogenesis of IBD is complicated, and it is widely accepted that immunologic, environmental and genetic components contribute to its etiology. To identify genetic susceptibility factors in CD, we performed a genome-wide association study in Japanese patients and controls using nearly 80,000 gene-based single nucleotide polymorphism (SNP) markers and investigated the haplotype structure of the candidate locus in Japanese and European patients. We identified highly significant associations (P = 1.71 x 10(-14) with odds ratio of 2.17) of SNPs and haplotypes within the TNFSF15 (the gene encoding tumor necrosis factor superfamily, member 15) genes in Japanese CD patients. The association was confirmed in the study of two European IBD cohorts. Interestingly, a core TNFSF15 haplotype showing association with increased risk to the disease was common in the two ethnic groups. Our results suggest that the genetic variations in the TNFSF15 gene contribute to the susceptibility to IBD in the Japanese and European populations.  相似文献   
37.
Gefitinib (Iressa, ZD1839), an inhibitor of epidermal growth factor receptor-tyrosine kinase, has shown potent anti-tumor effects and improved symptoms and quality-of-life of a subset of patients with advanced non-small cell lung cancer (NSCLC). However, a large portion of the patients showed no effect to this agent. To establish a method to predict the response of NSCLC patients to gefitinib, we used a genome-wide cDNA microarray to analyze 33 biopsy samples of advanced NSCLC from patients who had been treated with an identical protocol of second to seventh line gefitinib monotherapy. We identified 51 genes whose expression differed significantly between seven responders and 10 non-responders to the drug. We selected the 12 genes that showed the most significant differences to establish a numerical scoring system (GRS, gefitinib response score), for predicting response to gefitinib treatment. The GRS system clearly separated the two groups without any overlap, and accurately predicted responses to the drug in 16 additional NSCLC cases. The system was further validated by the semi-quantitative RT-PCR, immunohistochemistry and ELISA for serological test. Moreover, we proved that the anti-apoptotic activity of amphiregulin, a protein that was significantly over-expressed in non-responders but undetectable in responders, leads to resistance of NSCLC cells to gefitinib in vitro. Our results suggested that sensitivity of a given NSCLC to gefitinib can be predicted according to expression levels of a defined set of genes that may biologically affect drug sensitivity and survival of lung cancer cells. Our scoring system might eventually lead to achievement of personalized therapy for NSCLC patients.  相似文献   
38.
Patterns of linkage disequilibrium (LD) in the human genome are beginning to be characterized, with a paucity of haplotype diversity in "LD blocks," interspersed by apparent "hot spots" of recombination. Previously, we cloned and physically characterized the low-density lipoprotein-receptor-related protein 5 (LRP5) gene. Here, we have extensively analysed both LRP5 and its flanking three genes, spanning 269 kb, for single nucleotide polymorphisms (SNPs), and we present a comprehensive SNP map comprising 95 polymorphisms. Analysis revealed high levels of recombination across LRP5, including a hot-spot region from intron 1 to intron 7 of LRP5, where there are 109 recombinants/Mb (4882 meioses), in contrast to flanking regions of 14.6 recombinants/Mb. This region of high recombination could be delineated into three to four hot spots, one within a 601-bp interval. For LRP5, three haplotype blocks were identified, flanked by the hot spots. Each LD block comprised over 80% common haplotypes, concurring with a previous study of 14 genes that showed that common haplotypes account for at least 80% of all haplotypes. The identification of hot spots in between these LD blocks provides additional evidence that LD blocks are separated by areas of higher recombination.  相似文献   
39.
Marginal zone (MZ)-B cells participate in very early immune responses and play a pivotal role in the first-line of defense against blood-borne Ags including bacterial LPS. Since splenic B cells from c-fos transgenic (H2-c-fos) mice are hyper-sensitive to LPS stimulation, we examined LPS-sensitivity of MZ-B cells in the spleen of H2-c-fos mice. Here, we show that proliferation of MZ-B cells from H2-c-fos mice stimulated with LPS was larger than that from control mice. Proliferation and IgM production of the H2-c-fos MZ-B cells were also larger than those of splenic follicular (FO)-B cells from the H2-c-fos mice, suggesting that c-fos overexpression augments LPS-sensitivity of MZ-B cells more than that of FO-B cells. Furthermore, the number of MZ-B cells but not that of FO-B cells in the spleen of H2-c-fos mice was two- to three-fold larger than that in control littermates. The number of transitional type II (T2)-B cells in H2-c-fos mice was also larger than that of control littermates. However, the number of transitional type I (T1)-B cells in the spleen of H2-c-fos mice was not larger than that of control mice. Moreover, this c-fos effect on differentiation of MZ-B cells was intrinsic in B cells by the competitive repopulation assay with hematopoietic stem cells of H2-c-fos and control mice. These results suggest that c-fos overexpression in B cells augments differentiation and accumulation of MZ-B cells.  相似文献   
40.
Culture of chondrocytes in fibroin-hydrogel sponge   总被引:5,自引:0,他引:5  
Fibroin-hydrogel sponge and collagen gel were used as scaffold for in vitro cartilage regeneration. Fibroin-hydrogel sponge was formed by phase separation from freezed fibroin solution. Chondrocytes were harvested from proximal humerus, distal femur and proximal tibia of 4-week-old Japanese white rabbits and inoculated in the fibroin-hydrogel sponge and collagen gel. Those constructs were cultured in DMEM supplemented with 10% FCS and 50 ml L-ascorbate at 37 degrees C. Histological observation, measurement of sulfated glycosaminoglycan and cell density were carried out at 3, 7, and 14 days after the cultivation. Well-defined cartilage tissue can be seen both in the fibroin-hydrogel sponge and in the collagen gel. The matrix was intensely stained by safranin-O and showed a metachromatic reaction in both group. However, the quantity of sulfated glycosaminoglycan and cell density of the fibroin-hydrogel sponge group were increased more rapidly than these of the collagen gel group. Thus, the chondrocytes proliferated in the fibroin sponge without losing their differentiated phenotype. It is possible that culture environment in the fibroin sponge was suitable for chondrocytes regeneration.  相似文献   
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